At the broadest level, solar powers exponential rise is disrupting the traditional relationship every consumer has with its energy supply. With utilities running scared and the International Energy Agency (IEA) predicting big things in a very short space of time, solar power increasingly affordable, reliable, visible and accepted is set to shine more brightly as this decade ticks by.
But an encouraging offshoot of this growth has been the development of a range of innovative solar-powered products, devices and materials that are likely to ensure that solars expansion is anything but linear. A number of niche applications are fine-tuning their own take on solar PV, producing efficient, eco-friendly and increasingly useful solar-powered innovation.
Here are some niche solar inventions that have caught pv magazines eye in 2014.
Developed by researchers at the University of Sheffield in the U.K., spray-on solar cells that use perovskite to absorb PV light promise a lot of transformative potential in the solar industry, particularly the building integrated photovoltaic (BIPV) sector.
With a relatively modest cell efficiency of 11%, further improvement is needed before such a technique can be realistically commercialized, but in combining the high-efficiency and low cost of perovskite with a simple spray-on application, this technology could eventually bring low-cost solar energy to a range of industries. Researchers believe that efficiencies of 19% could be realistic within a couple of years, propelling spray-on solar into realistic competition with typical crystalline silicon solar cells.
Further research in this field has been conducted by scientists at the University of Toronto, who have focused on the use of colloidal quantum dots (CQD) on spray-on cells, rather than perovskite. CQDs flexible band gap can be tuned by altering the size of their nanoparticles, which means that more solar energy can be soaked up across a wider solar spectrum a potentially valuable addition to multi-junction solar cells.
Previously, using CQDs was an inefficient and expensive process, but the universitys researchers have developed an instrument that can spray dots on to any flexible surface such as plastic or film.
"My dream," said university post-doctoral fellow Illan Kramer, "is that one day youll have two technicians with Ghostbuster backpacks come to your house and spray your roof. Efficiency at the moment is just 7.2%, but as quantum dot technology advances, Kramer and his fellow scientists are confident that this process will be manufacturable within the decade.
U.K.-based startup The Solar Cloth Company has recently made headlines with its innovative solar cloth that the company claims can transform commercial rooftop space in the U.K. and beyond. Developed over the space of seven years to tackle the problem of utilizing the space of non-load bearing rooftops, the lightweight and flexible solar cloth can be retrofitted or integrated at construction to rooftops unable to take the strain of traditional solar panels.
The cloth can also be used on carports and other rooftops, such as stadiums, and the company is currently in the process of securing a contract to install its technology on some 27,000 parking lots in the U.K.
The lightweight cloth (which weighs around seven pounds per 10 square meter) utilizes CIGS technology and has 10.4% to 12.6% aperture efficiency, making it the company claims "50% more efficient than a flexible a-Si". Installing the solar cloth is also cost-effective, offering savings of between 30% and 40% when BOS costs are incorporated.
Peel and stick PV
As reported on pv magazine last week, peel and stick PV cells could revolutionize the BIPV sector. Developed by a team at Stanford University, the peel and stick cells boast a nanomaterial grapheme that is grown on to a nickel layer that separates it from the silicon or glass backing used in conventional thin film manufacture.
This additional nickel layer can then be peeled away from the silicon or glass following immersion in water, thus creating a solar cell that is just a couple of microns thick and a tenth of the overall thickness of conventional plastic wrap thin film cells. This process removes the need for base material, which typically accounts for more than a quarter of the cost of thin film cells.
In Hamburg, Germany, stands an apartment block that is covered in photobioreactor panels algae that uses sunlight to generate fuel. The SolarLeaf façade was developed by Colt International and SSC Ltd., and is a photobioreactor within glass panels that contain living micro-algae plants.
The algae absorbs C02 and daylight, and via a process of photosynthesis generates heat of 40c that is fed into the building. Algae that has served its heat function is then harvested and turned into biofuel.
"The SolarLeaf biofacade is a way of storing solar energy to use as fuel later," Jan Wurm, Europe research leader at Arup, which designed the panels, told the Guardian. "It is a pilot project with data being collected on energy production and usage until mid-2015."
Out with the red, in with the green: Londons iconic red phone booths may steadily be replaced over the coming years with the striking green booths from Solarbox a U.K. startup that has developed a solar-powered phone booth that can be used to charge cell phones.
The technology itself may not be groundbreaking, but the subversive idea to use solar power to transform crumbling and outmoded landmarks into something useful and attractive is a shining example of the transformative power of PV.
"The fact that solar panels have come down in price so dramatically has helped make a project like this possible," said Solarbox co-founder Harold Craston.
Solar telephone booths, solar roadways and solar cycle paths all perfect examples of this new line of thinking; a secondary offshoot that could not have been possible without the solar industrys meteoric rise in recent years.